I can't remember where I heard this, but - in a sentence - I believe the government exists to provide goods and services for which a citizen efficiently contract individually. (Because that is a single sentence, it is no doubt easy to find exceptions in it and problems with it, but I believe it is a reasonable, objective starting point.) For example, I - as an individual - cannot efficiently contract a court system, an defensive army, or roadways for my personal use.

Extending from that a bit, I recently heard a politician say the government should not be providing goods and services someone can secure via the internet. Again, a bit overly simplistic, but I agree with the general premise.

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